Organic devices having a charge transporting layer in a part thereof are studied, developed, and produced in many fields such as organic electroluminescent elements, organic EL elements, solar cells, actuators, organic sensors, electronic paper, touch panels and electrophotographic photosensitive members. Organic devices having a charge transporting layer are often provided with a thin film formed by coating a substrate with a coating solution with a charge transporting substance dissolved in an organic solvent. Also for a method for producing an electrophotographic photosensitive member that is one of organic devices, a method is generally used in which a coating liquid with a charge transporting substance dissolved in an organic solvent is made and applied onto a support. A charge transporting layer is often demanded for having durability, among the respective layers of a laminate type electrophotographic photosensitive member, and a coat of the layer has a thicker film thickness than other layers. Therefore, the amount of a coating liquid used is larger, thereby resulting in a charge transporting layer in which a large amount of an organic solvent is used. In order to reduce the amount of an organic solvent in producing an electrophotographic photosensitive member, it is desirable to reduce the amount of an organic solvent for use in a coating liquid for a charge transporting layer. However, in order to make the coating liquid for a charge transporting layer, a halogen solvent and an aromatic organic solvent are required to be used because of highly dissolving a charge transporting substance and a resin, and thus the amount of an organic solvent is reduced with difficulty.
PTL 1 relates to a coating material for forming a charge transporting layer and reports an approach for the purpose of reducing the amount of an organic solvent for reducing a volatile substance and carbon dioxide. This Literature discloses making of an emulsion for a charge transporting layer by charging into water an organic solution with substances contained in a charge transporting layer dissolved in an organic solvent and forming oil drops in this water.